Ariana Grande memorialized Mac Miller with a heartbreaking tribute Friday on Instagram, describing the late rapper as the “kindest, sweetest soul with demons he never deserved.”

Miller died on Sept. 7 of a suspected overdose after friends discovered his body at his San Fernando Valley home in California. Law enforcement officials have not given any official cause, as results from toxicology tests can take up to six weeks.

The 26-year-old artist candidly addressed substance abuse in his music. Grande has intimated the affliction was one of the reasons why their two-year relationship ended in May.

After breaking her silence on his death over the weekend, the “Sweetener” singer followed up the post with a short video of herself and Miller.

In the video, Miller discovers Grande is filming while he’s telling a story at the dinner table.

“I’ll tell you this story as many times as you want,” he says in the clip, as the two break out into laughter.

The singer made her first statement on his death in the caption below, explaining that she “can’t wrap my head around it,” despite the two frequently discussing the possibility when Miller was alive.

“i adored you from the day i met you when i was nineteen and i always will. i can’t believe you aren’t here anymore,” she wrote. “i really can’t wrap my head around it. we talked about this. so many times. i’m so mad, i’m so sad i don’t know what to do. you were my dearest friend. for so long. above anything else. i’m so sorry i couldn’t fix or take your pain away. i really wanted to. the kindest, sweetest soul with demons he never deserved. i hope you’re okay now. rest.”

A close friend of Miller’s described the pop star as “unbelievably involved” in keeping him sober and a “stabilizing force” in his recovery.

“They were very much in love, and I have to say she was incredible when he was first sobering up,” Miller’s friend Shane Powers said on his podcast. “She was a fucking G to him. There could not have been anybody more supportive of him being sober than Ariana. I saw that. I was around it.”

After two years of dating, Grande and Miller split in May. Shortly after the breakup, Miller crashed his car into a utility pole and fled the scene. Police arrested the rapper at his home hours later after he reportedly registered twice the legal limit of alcohol in his system.